The present invention relates to a racket stringing machine, and more particularly to an improved chucking mechanism of the racket stringing machine.
As shown in FIG. 1 provided herein, a racket stringing machine of prior art comprises a stationary chucking arm 12 provided thereon with a chucking means 14, which is composed of a base 16 pivotally attached to the chucking arm 12 and of a threaded rod 18 pivotally arranged at the top end of the base 16 and provided at front end thereof with a jaw 19. A racket frame can be clamped to or released from the chucking means 14 by rotating the threaded rod 18 in a forward direction or a backward direction. Such maneuvers are extremely time-consuming and inconvenient.
In addition, the chucking means 14 described above is not suitable for use in clamping a relatively new racket frame 10 as shown in FIG. 2. Such racket 10 has a frame of uneven thickness. For example, the points A and C of the frame have thickness of 22 mm respectively, while the points B and D of the frame have thickness of 30 mm respectively. As shown in FIG. 3, the racket frame 10 is held by the chucking means 14, with points B and D of the racket frame 10 positioned on the chucking arm 12 and with points A and C suspended. Therefore, points A, B, C and D must be clamped securely at the same time so that the racket 10 can be held firmly by the chucking means 14. However, points A and C are devoid of support and are therefore vulnerable to deformation when acted on with force.